/Engine/Plugins/Online/OnlineSubsystem/Source/Public/Interfaces/OnlineFriendsInterface.h
virtual [FDelegateHandle](API\Runtime\Core\Delegates\FDelegateHandle) AddOnBlockListChangeDelegate_Handle ( int32 LocalUserNum, const [FOnBlockListChangeDelegate](API\Plugins\OnlineSubsystem\Interfaces\FOnBlockListChangeDelegate) & Delegate )